Portable laundry dryer



July 12, 1966 R. D. HULL ETAL 3,259,996

PORTABLE LAUNDRY DRYER Filed Sept. 5, 1963 5 SheetsSheet 1 Fog Z. Hu// 27 Jerry F. Hw/

INVENTORS Z5 ATTORNEY July 12, 1966 R. D. HULL ETAL PORTABLE LAUNDRY DRYER Filed Sept. 5, 1963 5 Sheets-Sheet 2 INVENTORS Kid July 12, 1966 R. D. HULL ETAL PORTABLE LAUNDRY DRYER 5 Sheets-Sheet 5 Filed Sept. 5, 1963 65 R D /7u /?o L hu Jerry Hu INVENTOR5 ATTORNEY United States Patent 3,259,996 PORTABLE LAUNDRY DRYER R. Dell Hull, 3110 E. 33rd St.; Roy L. Hull, 3551 S. Toledo Place; and Jerry R. Hull, 3110 E. 33rd St, all of Tulsa 35, Okla.

Filed Sept. 5, 1963, Ser. No. 306,798 10 Claims. (Cl. 34-53) This application is a continuati0n-in-part of our copending application Serial No. 265,189, filed March 14, 1963 and now abandoned.

This invention relates to a laundry dryer and more particularly to a small portable dryer especially adapted for drying small items made of light fabrics, such as womens hose and lingerie.

Travelers, particularly women, generally follow the practice each day during a trip of washing out their hose and lingerie. To dry the wet garments, the usual practice is to hang them on suitable supports about a bathroom or other places where they present an unsightly appearance and are often a source of annoyance and inconvenience. Further, in areas of high humidity, the garments are often very slow drying, creating another source of inconvenience and annoyance. The primary objects of this invention are to provide a dryer which is of light, compact construction, especially adapted for use by travelers, and which is highly eflicient for drying light weight garments. 7

An important object is to provide a dryer employing a two-part telescoping casing, one part enclosing air-heating and circulating elements, the other, when extended, defining the dryingchamber adapted to receive the garments to be dried.

A further object is to provide in a dryer having a twopart telescoping casing as described, releasable latch means arranged between the casing portions to secure the portions in their relatively extended position.

Still another objectis the provision of a dryer of the general character described having an electrical circuit including electric heating and electric motor-driven fan elements, said electrical circuit being controlled by a timedelay switch constructed to selectively vary the time period of operation of said elements.

An additional object is the provision in a dryer of the general character described and employing a timecontrolled switch in the electrical circuit including the heating and air-circulating elements, of a time-control element comprising a highly viscous chemical composition consisting essentially of a silicone putty.

Other and more specific objects and advantages of this invention will become more readily apparent from the following detailed description when read in conjunction with the accompanying drawing which illustrates one useful embodiment in accordance with this invention.

In the drawings:

FIG. 1 is an elevational view, partly-sectional, showing the device with the sections of the casing in extended relation;

FIG. 2 is a top plan view of the device;

FIG. 3 is an elevational view, partly sectional, showing the casing sections in collapsed relation;

. FIG.-4 is a vertical cross-sectional view taken generally,

along line 44 of FIG. 2;

I FIGS. 5 and 6 are cross-sectional views taken generally along lines 55 and 6-6, respectively, of FIG. 4;

FIG. 7 is a vertical cross-sectional view taken generally I along line7-7 of FIG. 4; p

FIG. 8 is a side elevation of the switch elements of the device;

FIG. 9 is an enlarged vertical sectional View taken generally along line 9-9 of FIG. 8; and I 3,259,99fi Patented July 12, 1966 ice FIG. 10 is a circuti diagram of the electrical elements of the device.

Referring to the drawing, the dryer comprises a hollow, generally tubular casing, designated generally by the numeral 10, including an upper section 11 and a lower section 12, telescopically extending into the upper section. Upper section 11 is provided at its upper end with an opening 11a through which articles to be dried may be introduced into the casing. Opening 11a is spaced from the wall of the upper section by an annular rim 14a which is arcuate in cross-section with its concave surface facing downwardly. Opening 11a is provided with a cover 13, hinged at 14 to rim 14a the cover being provided with a plurality of openings 15 to permit escape of the moisture-laden air resulting from the drying of the articles. The peripheral portion of cover 13 is provided at a point opposite hinge 14 with a downwardly projecting tongue 13a having a short outwardly projecting lip 13b having a rounded nose adapted to latch under the edge of a flange 13c extending from rim 14a into opening 11a. The natural flexibility of the material from which tongue 13a is constructed and the rounded surfaces of lip 13b cooperate to enable the latter to be pushed or pulled past the edge of flange 130 by a small amount of force, in order to latch the cover in closed position or to release the cover for movement tothe opening position.

A base plate 16 is secured to the lower end of lower section 12 by suitable means and is provided with a plurality of openings 19 through which air may enter the casing. The wall of casing section 12 is provided with a plurality of openings 20 also for entrance of air into the casing. Lower casing section 12 is provided on the interior thereof with a plurality (three on centers) of vertically extending outwardly projecting portions 21 which define vertical splines which are receivable in correspondingly shaped grooves 22 provided in the inner wall of upper casing section 11. These splines serve as guides for relative longitudinal movement between upper casing section, 11 and lower casing section 12, while preventing relative rotation between these casing sections.

Upper casing section 11 is provided in the exterior thereof near its lower margin opposite the respective spline grooves, with thumb latches 23, mounted on intermediate pivots 23a (best seen in FIG. 5) for rocking movement of the ends of the latches toward and away from the exterior surface of the casing section. One end of each latch on one side of pivot 23a carries an inwardly extending tongue 24 which projects through a slot 25 in the facing portion of the casing wall into spline groove 22 and is adapted to enter a transverse latching slot 26 formed in spline '21 near its upper end when the casing sections are in extended relation (FIGS. 5 and 7) to lock the sections in this extended relation. Coil springs 27 are mounted between the exterior of the casing wall and the end portions of latches 23 on the opposite sides of pivots 23a from tongues 24 to normally urge tongues 24 inwardly so that when upper casing section 11 is raised to its extended position, bringing slots 26 opposite tongues24, the latter will automatically enter slots 26 to lock the casing sections in the extended relation. To release the latches to permit collapsing the casing sections, it is only necessary to depress the latches against the pressure of springs 27 to retract tongues 24 from slots 26 while applying light downward force to upper section 11.

The upper and lower casing sections are made to substantially'the same length so that in the retracted relation of the casing sections, the overall dimensions of the dryer are greatly reduced for convenience in packing it into a suitcase, or the like, when not in use. A screen 30 extends transversely across the upper portion of lower casing section 12 and is preferably of upwardly tapering conical or convex shape, the periphery of the screen being secured to an annular ledge 31 formed adjacent the upper end of lower casing section 12.

Mounted centrally on base plate 16 inside lower casing section 12 is an electrical motor 35 having a vertically extending shaft 36, to the end of which is secured a fan 37 having horizontaly disposed blades of any suitable and generally conventonal shape. The fan is located within the upper portion of lower section 12 beneath screen 30 and within the opening formed by the bore of ledge 31. The latter functions as an annular baflle encircling the blade tips of fan 37 in position to prevent recirculation of air about the tips of the fan when the latter is rotated, to thereby assure that the maximum volume of air delivered by the fan will be directed upwardly through screen 30.

An electrical heating coil 40 of any suitable and generally conventional design, such as a resistance wire coil, is disposed in lower casing section 12 preferably just below fan 37 in such position that air drawn by fan 37 through openings 19 and slots 20 will pass over coil 40 and be heated thereby before being delivered by fan 37 through screen 30 and thence through the interior of upper section 11 and out of openings 15 in cover 13. Coil 40 is mounted on suitable insulated supports 41 secured to the wall of lower casing section 12. Electrical leads 43' are connected to terminals 44 of a thermostat 47 for controlling the temperature of the heating element. A suitable source of electrical current 45 may be connected in a conventional manner to leads 43. A switch 46 is interposed in the circuit for connecting and disconnecting the current to the motor and heating element and is controlled by a novel form of time-delay device, designated generally by the numeral 50. FIG. 10 diagrams a circuit employed for the electrical apparatus.

Switch 46 may be of any generally well-known design suitable for the purpose of opening and closing the electrical circuit. For purpose of illustration, switch 46 may be a form marketed under the trade name Microswitch, actuation of which is effected by a slight displacement of a spring-loaded plunger 48 which projects from the switch housing. The switch includes terminals 49 for connection of leads 43, which may be connected so that switch 46 may be either normally open or normally closed as desired. For purposes of this description it will be assumed that the switch is normally open and the current cut off from the heating element and fan motor, when plunger 48 is depressed or pushed inwardly of the switch housing. When the plunger is in the outer or projected position, the switch will be closed allowing current to flow to the electrical elements.

The time-delay device 50 makes use, as a key functional element, of a substance having unique viscosity characteristics. A substance particularly useful in this case is silicone putty, commonly referred to as bouncing putty, under which designation it has been distributed and sold, primarily as a novelty item.

One particularly suitable substance is that commercially manufactured by Dow Corning Corporation, and designated as their Dow Corning C-4551, and is more fully described in the sales literature as follows:

Descriptin.-A medium-consistency, non-Newtonian silicone fluid composition commonly known as Bouncing Putty.

Typical properties:

Color Coral Plasticity .060.080 Rebound, percent 70-85 Ap. Gr. at 25 C. 1.2

The unique and novel viscosity characteristics of silicone putty are further described in U.S. Patent 2,768,253, wherein its application in time-delay switches is described. In the present application it is not intended to lay claim to any novelty for the use of this substance or in its general application to time-delay devices, but to a particular novel combination structure including a time-delay device employing this unique substance.

The time-delay device is employed to actuate plunger 48 of the switch which controls the electrical elements of the dryer and is best seen in FIGS. 7, 8 and 9.

Switch 46 and time-delay device 50 are both mounted on a metal frame 51 which is suitably mounted on base plate 16 and secured thereto as by means of the bolts 52. At one lower corner of frame 5-1, the latter is formed with a laterally extending cylinder 53 closed at its outer end by an end wall 54. J ournalled in the bore of cylinder 53 is a cylindrical shaft 55, substantially smaller in external diameter than the internal diameter of the cylinder 53, providing an annular space which is filled with a layer of silicone putty 56. The outer end of the annular space about shaft 55 is closed by a ring 57 which is pressed into a counterbore 58 in the cylinder and bears against a shoulder 59 on shaft 55 near its outer end. Shaft 55 is provided with an outwardly projecting portion formed as a spur gear 60. [For purposes of cost savings and ease of manufacture, shaft 55 and spur gear 60 may be integrally formed from a suitable plastic material, although it will be recognized that metal or other materials may be employed for constructing these parts either as integral par-ts or as separate parts. Gear 60 is adapted to mesh with a larger diameter spur gear 61 which is mounted to rotate about stub shaft 62 projecting laterally from frame 51 in a direction opposite cylinder 53. Spur gear 61 is provided with a tubular hub 63 which is rotatably received on shaft 62. Gear 6 1 is held in place on shaft 62 by means of a lock ring 64 which is pressed on the outer end of shaft 62 against the end of hub 63. A clutch plate 65 is mounted about hub 63 and is pressed into facing engagement with the outer face of gear 61 by means of a spring washer 66 backed by a lock ring 67. The inner face of clutch plate 65 carries a plurality of circumferentially arranged, angularly spaced rounded projections or nibs 68 which cooperate with a registering circular row of correspondingly shaped depressions 69 in the outer face of gear 61. The force of spring 66 is normally sufficient to friction ally hold nibs 68 in engagement in depressions 69 but upon application of a small rotative movement to clutch plate 65, clutch plate 65 can be turned through any desired angle relative to gear 61, the engagement of nibs 68 in depressions 69 at the new posit-ion serving to hold the clutch plate in the so-adjusted position relative to gear 61. Clutch plate 65 carries a radially projecting handle 70 by which the clutch plate may be rotated relative to gear 61. Extending from clutch plate 65, generally opposite to handle 70, is a crank arm or lug 711 which is adapted to be rotated in response to rotation of clutch plate 65 into and out of engagement with plunger 48. A coil spring 72 has one end connected to an arm 73 extending from frame 51 and has its other end secured to a crank pin 74 extending from the side of lug 711 to maintain a continuous biasing force tending .to rotate clutch plate 65 in a di-v rection to urge lug 71 toward plunger 48. Gear 61, clutch plate 65, lever 70- and lug 71 may all be constructed of suitable plastic materials or other materials as may be desired. As illustrated, clutch plate 65, lever 70 and lug 7l1 are integrally molded from plastic materials.

Operation of the time-delay device is as follows: Starting with lug 71 engaging plunger 48 to hold the latter in the normally open or off position, as shown in FIG. 7, handle 70 will be in the lowermost position. The handle will be lifted upwardly rotating lug 71 away from plunger 48, allowing the latter to project from the switch housing, seen in FIG. 8, thereby closing the circuit to the heating coil and to the fan motor, both of which are now caused to operate.

The angular distance between lug 71 and the plunger will determine the time which will elapse before lug 71 is returned to-the position shown in FIG. 7 under the biasing of coil spring 7-2 in opposition to the resistance developed by the internal viscosity of silicone putty 56 actingbetween the opposed surfaces of shaft 55 and the wall of cylinder 53. By positioning suitable indicia 75 alongside the path of movement of lever 70, the indicia being calibrated with respect to time, indexing of lug 71 relative to the indicia may be effected to provide any desired period of time delay. Thus longer or shorter drying periods may be employed as may be found desirable in each instance of use.

It is believed that the operation of the device will be evident from the foregoing. When not in use, the casing sections will be telescoped together, as illustrated particularly in FIG. 3, whereby the dryer will present a very compact structure of quite small dimensions. When it is to be used, the casing sections will be relatively extended until locked together, as previously described in the positions'shown in FIGS. 1, 4 and 7. The articles of clothing to be dried will then be introduced through opening 11a into upper casing section 11 by opening cover 13 and the latter will then be closed down to retain the articles within the casing. Leads 43 connected to the motor and heating elements will be plugged into current source 45. Switch 46 will be actuated by raising lever 70 to release plunger 48. This will close the electrical circuit and start fan 37 and heating of coil 40. The fan will then draw air from outside the device through openings 19 and slots 20 and will blow it upwardly through screen 30 and the articles of clothing inside upper section '11 of the casing. The air will be heated in pas-sage over coil 40 and this warm air will effectively dry the articles of clothing the resulting moisture-laden heated air being discharged through openings 15 in cover 13. Operation of the fan and heater will continue until lug 71 has rotated through its previous angular displacement and again strikes plunger 48, opening the electrical circuit and stopping the fan and heater. When the articles of clothing have been dried sufficiently, they will be removed from upper casing section 11 and the latter moved down back to its retracted position by depressing thumb latches 23.

The efficiency of the dryer is substantially enhanced by the combination of the upward conical taper of screen 30 with the arcuate concave shape of the rim portion 14a surrounding opening 11a. These relative shapes cause a recirculation of at least part of the warm air back down through the center of the mass of garments lying on the screen and thereby speeds the drying of the garments.

The heating element and the fan design will be selected to provide the air at the desired volume and temperature for most effective and rapid drying without damaging the usually delicate fabrics to be dried.

The parts of casing as well as all of the other elements of the device, except the electrical elements, will preferably be made of a suitably strong and light weight plastic, many types of which are available commercially. The dimensions of the device may be made quite small, since portability is one of the principal features. A dryer which has an external diameter of six to eight inches and a height of about the same dimension, when in collapsed or retracted condition, 'will be found most suitable for most cases, although it will be understood that somewhat larger dimensions may be employed where found desirable.

It will be understood that various changes and modifications may be made in the details of the illustrative embodiment within the scope of the appended claims but without departing from the spirit of the invention.

What we claim and desire to secure by Letters Patent is:

l. A portable laundry dryer, comprising, a lower tubular casing section having openings through the walls thereof for entrance of outside air, an upwardly tapering transverse foraminous wall across the upper portion of said lower casing section, an upper tubular casing section defining a drying chamber disposed about the lower casing section in telescoping relation for extension and retraction relative thereto, an inwardly extending annular rim about the upper end of said upper section defining a central opening in said upper end, said annular rim being arcuate in cross-section with its concave side facing downwardly, a perforate cover hinged to said rim for closing said central opening, releasable latch means constructed and arranged between the casing sections for securing said casing sections in relatively extended position, and means mounted in said lower casing section for heating and circulating air through said drying chamber, said means for circulating .air including a horizontally disposed fan rotatably mounted below said foraminous wall, and an annular bafile secured to the wall of the lower casing section about the periphery of the fan.

2. A portable laundry dryer according to claim 1 wherein said air-circulating and heating means includes an electric motor for driving said fan, an electric heating coil in circuit with said motor, and a variable time-delay switch controlling said circuit.

3. A portable laundry dryer according to claim 2 wherein said variable time-delay switch means includes a pair of concentric relatively rotatable elements, and a timedelay element comprising a body of silicone putty interposed between concentric surfaces of said elements.

4. A portable laundry dryer, comprising, a lower tubular casing section having openings through the walls thereof for entrance of outside air, an upwardly tapering transverse foraminous wall across the upper portion of said lower casing section, an upper tubular casing section defining a drying chamber disposed about the lower casing section in telescoping relation for extension and retraction relative thereto, a hinged perforate cover closing the upper end of said upper casing section, releasable latch means constructed and arranged between the casing sections for securing said casing sections in relatively extended position, and electrical means mounted in said lower casing section for heating and circulating air through said drying chamber, said last mentioned means including an electrically driven, horizontally disposed fan rotatably mounted below said foraminous wall, an annular bafiie secured to the wall of the lower casing section about the periphery of the fan, an electric heating coil mounted in said lower casing section in the path of movement of said air toward the drying chamber, and deflector means disposed in the path of said circulating air constructed and arranged to cause recirculation of at least a part of the air in said drying chamber.

5. A portable laundry dryer according to claim 4, wherein said electrical means includes a circuit connecting said fan and said heating coil, and variable timedelay switch means controlling said circuit.

6. A portable laundry dryer according to claim 5, wherein said variable time-delay switch means includes a pair of concentric relatively rotatable elements, and a time-delay element comprising a body of silicone putty interposed between concentric surfaces of said elements.

7. A portable laundry dryer, comprising, a lower tubular casing section having openings through the walls thereof for entrance of outside air, a transverse foraminous wall across the upper portion of said lower casing section, an upper tubular casing section defining a drying chamber disposed about the lower casing section in telescoping relation for extension and retraction relative thereto, a perforate cover means removably closing the upper end of said upper casing section, releasable latch means constructed and arranged between the casing sections for securing said casing sections in relatively extended position, and electrical means mounted in said lower casing section for heating and circulating air through said drying chamber, said electrical means including an electric motor-driven fan in circuit with an electric heater, and variable time-delay switch means controlling said circuit, said switch means including a movable contact for opening and closing the same, a first rotatable gear, a clutch plate frictionally engaging a face of said first gear and angularly adjustable relative thereto, a second gear in mesh with said first gear, a cylindrical shaft mounting said second gear, a cylindrical housing enclosing said shaft, a body of silicone putty filling said housing about said shaft, cam means carried by said clutch plate for movement therewith into and out of engagement with said movable contact, and means applying a cont-inuous biasing force to said clutch plate in a direction to urge said cam means toward said movable contact.

8. A portable laundry dryer according to claim 7 wherein said casing sections are of substantially the same length.

9. A portable laundry dryer according to claim 7 wherein said releasable latch means comprises a plurality of angularly spaced latches pivotally mounted on the exterior of the upper casing sections and carrying tongue portions projecting inwardly through the wall of said upper casing section toward cooperating recesses in the lower casing section, and biasing means resiliently urging said tongue portions inwardly.

10. For use in heating and circulating air, the sub: combination, comprising, an electric motor-driven fan in circuit with an electric heater, and variable time-delay 25 switch means for controlling said circuit, said switch means having a movable contact for opening and closing the same, a first rotatable gear, a clutch plate frictionally engaging a face of said first gear and angularly adjnstble relative thereto, a second gear in mesh with said first gear, a cylindrical shaft mounting said second gear, a cylindrical housing enclosing said shaft, a body of silicone putty filling said housing about said shaft, cam means carried by said clutch plate for movement therewith into and out of engagement with said movable contact, and means applying a continuous biasing force to said clutch plate in a direction to urge said cam means toward said movable contact.

References Cited by the Examiner UNITED STATES PATENTS 51,562 12/1865 Crane 34-233 928,055 7/1909 Johnson et al. 285 317 2,253,475 8/ 1941 Willber. 2,438,762 3/ 1948 McLeckie 34202 2,517,254 8/ 1950 Steele 1269 2,701,921 2/1955 Strongson 34151 2,768,253 10/1956 Broch 200169 3,054,194 9/ 1962 Hayes 3453 WILLIAM F. ODEA, Primary Examiner.

A. D. HERRMANN, Assistant Examiner. 

1. A PORTABLE LAUNDRY DRYER, COMPRISING, A LOWER TUBULAR CASING SECTION HAVING OPENINGS THROUGH THE WALLS THEREOF FOR ENTRANCE OF OUTSIDE AIR, AN UPWARDLY TAPERING TRANSVERSE FORAMINOUS WALL ACROSS THE UPPER PORTION OF SAID LOWER CASING SECTION, AN UPPER TUBULAR CASING SECTION DEFINING A DRYING CHAMBER DISPOSED ABOUT THE LOWER CASING SECTION IN TELESCOPING RELATION FOR EXTENSION AND RETRACTION RELATIVE THERETO, AN INWARDLY EXTENDING ANNULAR RIM ABOUT THE UPPER END OF SAID UPPER SECTION DEFINING A CENTRAL OPENING IN SAID UPPER END, SAID ANNULAR RIM BEING ARCUATE IN CROSS-SECTION WITH ITS CONCAVE SIDE FACING DOWNWARDLY, A PERFORATE COVER HINGED TO SAID RIM FOR CLOSING SAID CENTRAL OPENING, RELEASABLY LATCH MEANS CONSTRUCTED AND ARRANGED BETWEEN THE CASING SECTIONS FOR SECURING SAID CASING SECTIONS IN RELATIVELY EXTENDED POSITION, AND MEANS MOUNTED IN SAID LOWER CASING SECTION FOR HEATING AND CIRCULATING AIR THROUGH SAID DRYING CHAMBER, SAID MEANS FOR CIRCULATING AIR INCLUDING A HORIZONTALLY DISPOSED FAN ROTATABLY MOUNTED BELOW SAID FORAMINOUS WALL, AND AN ANNULAR BAFFLE SECURED TO THE WALL OF THE LOWER CASING SECTION ABOUT THE PERIPHERY OF THE FAN. 